Vrtc Interface - Quectel SC20-WL Hardware Design

VBAT
PWRKEY
Others

3.6. VRTC Interface

The RTC (Real Time Clock) can be powered by an external power source through VRTC when the
module is powered down and there is no power supply for the VBAT. The external power source can be
capacitor or rechargeable battery (such as coil cells) according to application demands. The following are
some reference circuit designs when an external battery or capacitor is utilized for powering RTC.
Large
Capacitance
Capacitor
SC20-WL_Hardware_Design
Figure 9: Timing of Turning off Module
Coin Cell
Figure 10: RTC Powered by Coin Cell
C
Figure 11: RTC Powered by Capacitor
>8s
Power down
VRTC
Module
VRTC
Module
Smart Wi-Fi Module Series
SC20-WL Hardware Design
RTC
Core
RTC
Core
34 / 81